Plum tree named ‘August Yummy’

ABSTRACT

The present invention relates to a plum tree,  Prunus salicina,  and more particularly to a new and distinct variety broadly characterized by a medium size, vigorous, hardy, self-unfruitful, heavy blooming, pollen abundant, and usually productive tree that may be cross pollinized by ‘Blackamber’ (unpatented). The fruit matures under the ecological conditions described during mid August, with first picking on Aug. 11, 2002, but will hang on the tree for nearly twenty more days. The fruit is uniformly large in size, dark red in skin color, clingstone in type, yellow with some red bleeding in flesh color, very firm and crisp in texture, very good in flavor, and holds well in cold storage for more than thirty days. The variety was developed as a first generation cross using ‘Grand Rosa’ (U.S. Plant Pat. No. 1,756) plum as the selected seed parent and an undetermined plum as the pollen parent.

Botanical classification: Prunus salicina.

Variety denomination: ‘August Yummy®’.

BACKGROUND OF THE VARIETY

In a continuing effort to improve the quality of shipping fruits, I, theinventor, typically hybridize a large number of peach, nectarine, plum,apricot, and cherry seedlings each year. I also grow a lesser number ofopen pollinated seeds of each of these fruits. The present inventionrelates to a new and distinct variety of plum tree, which has beendenominated varietally as ‘August Yummy®’. Yummy® is a U.S. Trademark,application Ser. No. 75/618,722, owned by Johnny Appleseed HoldingsLimited, Saint Georges Road South RD2, Hastings, New Zealand. Permissionto use has been granted to the applicant by contract.

During a typical blooming season I isolate as seed parents bothindividual and groups of different plum trees by covering them withscreen houses. A hive of bees is placed inside each such house andbouquets to provide pollen from different plum, apricot, andplum-apricot hybrid trees are placed near the trees approximately everythree days for the duration of the bloom. During 1996 one such housewith a tree of ‘Grand Rosa’ (U.S. Plant Pat. No. 1,756) was crossed byme in this manner. To pollinate this ‘Grand Rosa’ tree, I selectedbouquets from several sources that season without keeping writtendetails. Upon reaching maturity the fruit from this ‘Grand Rosa’ treewas harvested and the seeds were removed, cracked, stratified andgerminated as a group with the label “42PH11”. They were grown asseedlings on their own root in my greenhouse and, upon reachingdormancy, transplanted to a cultivated area of my experimental orchardat Bradford Farms near Le Grand, Calif. in Merced County (San JoaquinValley). During the summer of 2000, the present variety was selected asa single plant from the group of seedlings described above. Therefore,the variety was developed as a first generation cross using ‘Grand Rosa’(U.S. Plant Pat. No. 1,756) plum as the selected seed parent and anundetermined plum as the pollen parent. Subsequent to origination of thepresent variety of plum tree, I asexually reproduced it by budding andgrafting in the experimental orchard described above, and suchreproduction of plant and fruit characteristics were true to theoriginal plant in all respects. The reproduction of the variety includedthe use of ‘Nemaguard’ (unpatented) rootstock upon which the presentvariety was compatible and true to type.

The present variety is most similar to its seed parent, ‘Grand Rosa’(U.S. Plant Pat. No. 1,756), by being self-unfruitful and by producingplums that are globose to oblate in shape, mostly red in skin color, andyellow with some red bleeding in flesh color but is distinguishedtherefrom and an improvement thereon by producing plums that areclingstone instead of semi-freestone, that are smoother in skin surface,that are sweeter in flavor, that do not have a tendency to tip crack,and that mature about 3 weeks later.

SUMMARY OF VARIETY

The present plum variety is characterized by a medium size, vigorous,hardy, and usually productive tree. Being self-unfruitful, the presentvariety requires cross pollinization from another plum that bloomsduring the mid season, such as ‘Blackamber’ (unpatented). The presentvariety's abundance of blossoms and pollen entices strong bee activityto facilitate pollination. The fruit matures under the ecologicalconditions described during mid August, with first picking on Aug. 11,2002, but will hang on the tree for nearly twenty more days. The fruitis uniformly large in size, dark red in skin color, clingstone in type,yellow with some red bleeding in flesh color, very firm and crisp intexture, very good in flavor, and holds well in cold storage for morethan thirty days.

DRAWING

The accompanying photograph exhibits four whole fruits positioned todisplay the characteristics of the skin color and form, one fruitdivided transversely to the suture plane to reveal the flesh and stone,and typical leaves.

DETAILED BOTANICAL DESCRIPTION

Referring now more specifically to the pomological characteristics ofthis new and distinct variety of plum tree, the following has beenobserved under the ecological conditions prevailing near Le Grand,Merced County (San Joaquin Valley), Calif., and was developed at thestate of firm ripe on Aug. 15, 2002, on the original tree during itssixth growing season. All major color code designations are by referenceto the Inter-Society Color Council, National Bureau of Standards. Commoncolor names are also used occasionally.

TREE

Size: Medium, reaching and maintaining a height of 11′ [3.4 m.] and aspread of 7′ [2.1 m.] after six growing seasons utilizing typicaldormant pruning.

Vigor: Vigorous, responding typically to irrigation and fertilization.The variety grows about 4′ [1.2 m.] of surplus top-growth during thespring and summer. The plant should be grown on a standard commercialrootstock for production purposes.

Growth: Upright and open.

Form: Vase formed.

Hardiness: Hardy with respect to central California winters.

Heat tolerance: Observed to perform adequately in typical centralCalifornia climatic conditions, which typically include prolongedperiods of heat.

Drought tolerance: Variety is developed for commercial orchards andrequires regular irrigation.

Production: Very productive, thinning usually necessary.

Fertility: Self-unfruitful, requiring cross pollination by a suitablemid seasonal blooming plum, such as ‘Blackamber’ (unpatented).

Bearing: Usually consistent, but some uncertainty exists if inclementweather is encountered during the blooming period.

Trunk:

Size.—Medium, reaching a maximum diameter of 2¾″ [70 mm.] after thesixth growing season.

Texture.—Shaggy.

Bark color.—Dark grayish brown [62. d.gy.Br] with Light brown [57. l.Br]crevices streaked throughout.

Lenticels.—Approximate Number Per Square Inch: 18. Color: Moderateorange [53. m.O]. Typical Size: ⅛″ to ⅜″ [3.2-9.5 mm.].

Branches:

Size.—Diameter of limb is 1¼″ [32 mm.] measured 12″ above the secondaryfork, typical of Prunus salicina, and dependent upon cultural practicesand climatic conditions.

Texture.—Smooth on first year wood, rough on second year wood, shaggy onolder wood.

Color.— lst Year Wood Topside: Moderate brown [58. m.Br] where exposedto sunlight. 1st Year Wood Underside: Strong yellow green [117. s.YG].Older Wood: Dark yellowish brown [78. d.yBr] with some Strong yellowishbrown [74. s.yBr] crevices streaked throughout.

Lenticels.—Number Per Square Inch: Up to 80. Color: Light yellowishbrown [76. l.yBr]. Typical size: {fraction (1/32)}″ to {fraction(3/16)}″ [0.8-4.8 mm.].

Leaves:

Size.—Medium to large. Average Length: 3¾″ [95 mm.]. Average width:1{fraction (15/16)}″ [49 mm.].

Arrangement.—Alternate.

Thickness.—Medium.

Form.—Elliptical.

Apex.—Acuminate.

Base.—Rounded to acute, with an average angle base angle of 90 degrees.

Surface.—Smooth.

Color.—Dorsal Surface: Moderate olive green [125. m.OlG]. VentralSurface: Moderate yellow green [120. m.YG].

Margin.—Finely serrate.

Venation.—Pinnately net veined.

Petiole.—Average Length: {fraction (1/12)}″ [12.7 mm.]. AverageThickness: {fraction (1/16)}″ [1.6 mm.]. Color: Light yellow green [119.lYG] with Moderate reddish brown [43. m.rBr] tinting if exposed tosunlight.

Stipules.—Number: Almost always 2 per leaf. Average Length: ¼″ [6.4mm.]. Color: Brilliant yellow green [116. brill.YG] becoming Darkreddish brown [44. d.rBr] with age.

Glands.—Number: 2 to 6 per leaf. Position: Mostly alternate, fewopposite, positioned on the petiole and blade. Size: Small. Form:Globose. Color: Strong reddish brown [40. s.rBr].

Leaf buds.—Conic.

Flower buds:

Hardiness.—Hardy, with respect to central California winters.

Diameter.—Typically {fraction (3/16)}″ [4.8 mm.] 1 week before bloom.

Length.—Typically ⅜ [9.5 mm.] 1 week before bloom.

Form.—Not appressed.

Surface.—Pubescent.

Color.—White [263. White].

Flowers: Perfect, complete, perigynous, usually a single pistil,typically thirty or more stamens, five sepals and petal locationsalternately positioned.

Average flower diameter.—{fraction (11/16)}″ [17.5 mm.].

Number of petals.—Five, no double blossoms observed.

Petal shape.—Circular.

Petal margin.—Wavy.

Average petal diameter.—{fraction (7/16)}″ [11.1 mm.].

Average petal length.—⅜″ [9.5 mm.].

Petal apex.—Rounded.

Petal base.—Rounded.

Petal color.—White [263. White].

Anther color.—Brilliant yellow [83. brill.Y].

Stigma color.—Light greenish yellow [101. lgy].

Sepal color.—Light yellow green [119. lYG].

Sepal length.—{fraction (5/32)}″ [4 mm.].

Sepal width.—⅛″ [3 mm.].

Average pistil length.—⅜″ [9.5 mm.].

Average stamen length.—{fraction (5/16)}″ [7.9 mm.].

Fragrance.—Moderate.

Pollen production.—Abundant.

Blooming period.—Medium compared with other varieties, two days before‘Santa Rosa’ (unpatented).

Onset of bloom.—One percent on Feb. 20, 2002.

Date of full bloom.—Mar. 5, 2002.

Duration of bloom.—One to two weeks, dependent on ambient temperature.

Number per cluster.—3 to 9, average 5.

FRUIT

Maturity when described: Firm ripe, Aug. 15, 2002.

Date of first picking: Aug. 11, 2002.

Date of last picking: Aug. 25, 2002.

Size: Uniform, large.

Average diameter axially.—2{fraction (5/16)}″ [58.7 mm.].

Average diameter across suture plane.—2⅝″ [66.7 mm.].

Typical weight.—5.9 ounces [167 grams].

Form: Uniform, symmetrical, somewhat oblate.

Longitudinal section form.—Elliptical, compressed axially.

Transverse section through diameter.—Circular.

Suture: An inconspicuous line located in a very shallow groove extendingfrom the base and discontinuing at the pistil point.

Ventral surface: Rounded, slightly lipped toward the apex.

Lips: Fairly equal.

Cavity: Flaring, circular, suture showing on one side.

Depth.—{fraction (7/16)}″ [11.1 mm.].

Breadth.—1″ [25.4 mm.].

Base: Truncate.

Apex: Usually truncate with a small hump just before the pistil point.

Pistil point: An inconspicuous dot.

Stem: Medium.

Average length.—⅜″ [9.5 mm.].

Average width.—{fraction (3/32)}″ [2.4 mm.].

Skin:

Thickness.—Medium.

Surface.—Smooth.

Tenacity.—Tenacious to flesh.

Astringency.—Slight.

Tendency to crack.—Very slight.

Color.—Very dark red [17. v.d.R] smoothly blending to Dark red [16. d.R]with occasional Moderate yellow [87. m.Y] sun protected areas and smallPale orange yellow [73. p.OY]freckling throughtout.

Bloom.—Abundant.

Flesh:

Color.—Light yellow [86. l.Y] with a varying degree of Moderate red[1.5. m.R] streaking toward the skin that increases with maturity.

Surface of pit cavity.—Covered with short Pale yellow [89. p.Y] fibersthat break away from the stone when strongly twisted.

Amygdalin.—Moderate.

Juice.—Abundant, rich.

Texture.—Very firm and crisp, will hang 20 days on tree.

Fibers.—Abundant, fine.

Ripens.—Fairly even.

Flavor.—A blend of medium acid and high sugar, typically 18 to 21 brix.

Aroma.—Slight.

Eating quality.—Very good.

STONE

Type: Clingstone.

Form: Oval.

Hilum: Narrow, oblong.

Base: Straight.

Apex: Obtusely wedge shaped with a average angle of 110 degrees.

Sides: Equal.

Surface: Rough with no pitting or grooves.

External color of stone: Light grayish yellowish brown [79. l.gy.yBr].

Pit wall color when cracked: Light brown [57. l.Br].

Cavity surface color: Moderate brown [58. m.Br].

Average pit wall thickness: {fraction (1/16)}″ [1.6 mm.].

Average width: ⅝″ [15.9 mm.].

Average length: 1″ [25.4 mm.].

Average breadth: ⅜″ [9.5 mm.].

Tendency to split: Slight.

Kernel:

Form.—Oval.

Skin color.—Pale yellow [89. p.Y] when first cracked.

Pellicle color.—Light brownish gray [63. l.brGy].

Vein color.—Light brownish gray [63. l.brGy].

Taste.—Bitter.

Viable.—Yes.

Average width.—{fraction (7/16)}″ [11.1 mm.].

Average length.—{fraction (9/16)}″ [14.3 mm.].

Amygdalin.—Abundant.

USE

Market: Fresh market and long distance shipping.

Keepinq quality: Excellent. Fruit quality observed to remain in goodcondition in after 30 days in standard cold room at 36° Fahrenheit [2°Celsius].

Shipping quality: Excellent.

Resistance to insects: No unusual susceptibilities noted.

Resistance to diseases: No unusual susceptibilities noted.

Other Notes

Although the new variety of plum tree possesses the describedcharacteristics under the ecological conditions at Le Grand, Calif., inthe central part of the San Joaquin Valley, it is to be expected thatvariations in these characteristics may occur when farmed in areas withdifferent climatic conditions, different soil types, and/or varyingcultural practices.

I claim:
 1. A new and distinct variety of plum tree, substantially asillustrated and described, that is most similar to its seed parent,‘Grand Rosa’ U.S. Plant Pat. No. 1,756), by being self-unfruitful and byproducing plums that are globose to oblate in shape, mostly red in skincolor, and yellow with some red bleeding in flesh color but isdistinguished therefrom and an improvement thereon by producing plumsthat are clingstone instead of semi-freestone, that are smoother in skinsurface, that are sweeter in flavor, that do not have a tendency to tipcrack, and that mature about 3 weeks later.